This is a working overview of Prohibited substance, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-03-05 and is reviewed periodically as new material appears.
Cardarine is prohibited in competitive sport under the World Anti-Doping Agency code, where it is classified as a metabolic modulator. It is not approved as a prescription medicine in the United States, European Union, or other major markets. Regulatory action has focused on its presence in sports and in products marketed as research chemicals. Because it has no accepted medical indication, supply is often unregulated. This status creates legal and safety uncertainties for anyone who encounters the substance.
Anti-doping laboratories detect GW501516 and its metabolites using liquid chromatography-tandem mass spectrometry. Urine is the most common matrix, though blood and dried blood spots may also be used in some programs. Detection depends on factors such as dose, timing, metabolism, and the sensitivity of the assay. Published methods describe limits of detection in the low nanogram per milliliter range for related compounds. Exact detection windows are not fixed for all situations and remain an area of ongoing study.
Products sold as cardarine have been found to contain incorrect compounds, variable amounts, or no active ingredient at all. Independent testing is required to verify identity and purity. Common analytical approaches include high-performance liquid chromatography, mass spectrometry, and nuclear magnetic resonance for structural confirmation. These methods can distinguish GW501516 from related PPAR agonists and from unrelated steroids. For regulators and researchers, such verification is central to interpreting both biological results and adverse event reports.
GW501516 binds and activates PPARδ, a nuclear receptor that influences transcription of genes involved in fatty acid oxidation and energy use. Activation shifts some metabolic pathways in preclinical models, which is why the compound has been studied for lipid disorders and exercise-related endpoints. The exact downstream effects in humans are incompletely mapped. PPARδ is expressed in many tissues, including skeletal muscle, liver, and adipose tissue, so broad activation may have varied consequences. Researchers continue to examine how selective or partial activation might alter the balance between benefits and risks.
Published human data are sparse and mostly come from early-phase trials. Those studies examined short-term changes in lipids, glucose, and exercise capacity, but they were not large enough to establish efficacy or long-term safety. Some animal experiments reported increased running endurance, yet such findings do not prove a performance benefit in people. Anti-doping laboratories detect GW501516 and its metabolites in urine or blood using liquid chromatography-tandem mass spectrometry. Detection windows depend on dose, sample type, and individual metabolism. The method is sensitive enough to identify trace residues in tested samples.
Laboratory handling focuses on identity, purity, and stability. Reference standards are typically stored cold and dry, protected from light, because solutions can degrade over time. Analytical checks may use high-performance liquid chromatography with ultraviolet detection or mass spectrometry. Impurities and related substances can be separated chromatographically and compared with a known standard. Because cardarine is not an approved drug, compendial monographs are absent, and laboratories often rely on in-house methods. Reported purity varies among unregulated products and should not be assumed from a label.
| Property | Value | Notes |
|---|---|---|
| Regulatory status | Prohibited in sport | Listed by WADA as a metabolic modulator. |
| Approved medical use | None in major jurisdictions | Not a registered drug. |
| Common test matrix | Urine | Most anti-doping samples use urine. |
| Typical detection method | LC-MS/MS | Detects parent compound and metabolites. |
| Reference standard storage | -20 °C, desiccated | Typical for analytical standards. |
Cardarine is a common name for the investigational chemical GW501516, also written GW-1516. It was developed as a peroxisome proliferator-activated receptor delta agonist for metabolic conditions such as dyslipidemia. Early research focused on lipid handling and energy use in skeletal muscle and other tissues. The compound was never approved as a medicine. In public discussion, it is often grouped with performance-enhancing substances, although its receptor target differs from that of anabolic steroids or selective androgen receptor modulators. Regulatory and health authorities have issued warnings about its use.
GW501516 acts on PPARδ, a nuclear receptor that helps regulate fatty acid oxidation and energy homeostasis. In animal studies, activation of this receptor was associated with increased endurance and changes in lipid metabolism. Human trials examined effects on blood lipids and other metabolic markers, but the compound did not advance to approval. Rodent studies later reported tumors in multiple tissues at doses used in those experiments. Whether those findings translate to human risk remains uncertain, and the clinical relevance of the animal data is still debated.
PPARδ is a nuclear receptor that regulates gene expression related to fatty acid oxidation, glucose homeostasis, and mitochondrial function. GW501516 binds to this receptor with high affinity and activates downstream signaling in skeletal muscle and other tissues. Animal studies reported increased endurance and altered fuel preference, but human data remain limited and inconsistent. The precise relationship between receptor activation and observed physiological changes is still an area of active investigation. Researchers have also examined whether the compound affects inflammation or cell proliferation. No approved therapeutic indication exists for cardarine.
In laboratory settings, cardarine is studied as a tool compound for probing PPARδ biology. Published experiments often use cell cultures, rodent models, or isolated tissues. Some investigations focus on metabolic effects, while others assess potential risks such as carcinogenicity observed in long-term animal studies. Because human trials are sparse, most knowledge comes from preclinical work and adverse event reports. Scientific literature frequently notes the gap between animal findings and human outcomes. The compound is not a dietary supplement and is not intended for human consumption.
A number of these women would go on to join a class action lawsuit, Madrigal v. Quilligan, discussed below. These Mexican and Mexican-American women were given the stereotype as "hyper-fertile" and were believed to lack the knowledge of birth control methods due to the high numbers of teen pregnancies occurring within their community. At the Hospital of LA County+USC, coercive sterilization was justified as it was an attempt to control the birthrate of these women. In 1998 the US government performed a census and multiyear analysis of Latino births and found the women of Mexican origin displayed the highest rate of childbirth compared to other Latina women. From these statistics, the "Save our State" campaign arose and worked to enforce more eugenic sterilization of these women. In 1973 an investigation by progressive anti-sterilization advocacy groups discovered the stories of Mary Alice's and Minnie Lee Relf's sterilization. This story was released by the Southern Poverty Law Center and led to the discovery of 16 thousand women and 8,000 men being sterilized using federal funds in 1972. In addition to this finding, they found more than three hundred of these patients were under the legal age of 21. Following this discovery and exposure, in 1977 Mexican-American began coming forth to file lawsuits in relation to coercive sterilization they faced while in labor. In 1979 a bill to repeal the eugenics laws passed that legalized sterilization was proposed to the legislature in California.
It is an optical analytical technique that analyzes the interference pattern of white light reflected from two surfaces: a layer of immobilized protein on the biosensor tip, and an internal reference layer. Any change in the number of molecules bound to the biosensor tip causes a shift in the interference pattern that can be measured in real-time, providing detailed information regarding the kinetics of association and dissociation of the two molecules as well as the affinity constant for the protein interaction (ka, kd and Kd). Due to sensor configuration, the technique is highly amenable to both purified and crude samples as well as high throughput screening experiments. The detection method can also be used to determine the molar concentration of analytes. Protein activity determination by NMR multi-nuclear relaxation measurements, or 2D-FT NMR spectroscopy in solutions, combined with nonlinear regression analysis of NMR relaxation or 2D-FT spectroscopy data sets. Whereas the concept of water activity is widely known and utilized in the applied biosciences, its complement—the protein activity which quantitates protein–protein interactions—is much less familiar to bioscientists as it is more difficult to determine in dilute solutions of proteins; protein activity is also much harder to determine for concentrated protein solutions when protein aggregation, not merely transient protein association, is often the dominant process.
Non-lamellar phases are known as non-bilayer liquid-crystalline phases without lamellar symmetry (Lα). They include hexagonal (I), hexagonal (II), and three-dimensional cubic phases. Hexagonal (I) phases are non-inverted or oil-in-water phases in which a net convex curvature is present and this is similar to micelles. Hexagonal(II) phases are inverted water-in-oil phases with net concave curvatures describing the lipid and water interactions. Cubic phases (Pn3m, Im3m, la3d, etc.) or bicontinuous cubic phases composed of multiple connected bilayers that resemble a three-dimensional cube. The presence of non-lamellar lipids in biomembranes affect the elasticity of the lipid bilayer, especially when it is disrupted, for example during phase transitions, membrane fusion and fission or interactions with membrane peptides and proteins.
Sources: en.wikipedia.org
=== Diagnostic testing === Vitamin C content in plasma is used to determine vitamin status. For research purposes, concentrations can be assessed in leukocytes and tissues, which are normally maintained at an order of magnitude higher than in plasma via an energy-dependent transport system, depleted slower than plasma concentrations during dietary deficiency and restored faster during dietary repletion, but these analyses are difficult to measure, and hence not part of standard diagnostic testing.
=== Ocular hypertension === Ocular hypertension (increased pressure within the eye) is an important risk factor for glaucoma, but only about 10–70% of people, depending on ethnic group, with primary open-angle glaucoma actually have elevated ocular pressure. Ocular hypertension—an intraocular pressure above the traditional threshold of 21 mmHg (28 hPa) or even above 24 mmHg (32 hPa)—is not necessarily a pathological condition, but it increases the risk of developing glaucoma. A study with 1636 persons aged 40–80 who had an intraocular pressure above 24 mmHg in at least one eye, but no indications of eye damages, showed that after five years, 9.5% of the untreated participants and 4.4% of the treated participants had developed glaucomatous symptoms, meaning that only about one in 10 untreated people with elevated intraocular pressure will develop glaucomatous symptoms over that period. Given these results, the clinical decision to treat everyone with elevated intraocular pressure with glaucoma therapy as a preventative measure is a matter of debate. As of 2018, most ophthalmologists favored treatment of those with additional risk factors. For eye pressures, a value of 28 hPa (21 mmHg) above atmospheric pressure 1,010 hPa (760 mmHg) is often used, with higher pressures leading to a greater risk. However, some may have high eye pressure for years and never develop damage. Conversely, optic nerve damage may occur with normal pressure, known as normal-tension glaucoma.
The main symptom of osteogenesis imperfecta is fragile, low mineral density bones; all types of OI have some bone involvement. In moderate and especially severe OI, the long bones may be bowed, sometimes extremely so. The weakness of the bones causes them to fracture easily—a study at the Endocrine Unit at the National Institute of Child Health in Karachi, Pakistan found an average of 5.8 fractures per year in untreated children. Fractures typically occur much less after puberty, but begin to increase again in women after menopause and in men between the ages of 60 and 80. Joint hypermobility is also a common sign of OI, thought to be because the affected genes are the same as those that cause some types of Ehlers–Danlos syndrome.
Sources: en.wikipedia.org
It is difficult or impossible to reliably evaluate whether an advanced AI is sentient (has the ability to feel), and if so, to what degree. But if there is a significant chance that a given machine can feel and suffer, then it may be entitled to certain rights or welfare protection measures, similarly to animals. Sapience (a set of capacities related to high intelligence, such as discernment or self-awareness) may provide another moral basis for AI rights. Robot rights are also sometimes proposed as a practical way to integrate autonomous agents into society. In 2017, the European Union considered granting "electronic personhood" to some of the most capable AI systems. Similarly to the legal status of companies, it would have conferred rights but also responsibilities. Critics argued in 2018 that granting rights to AI systems would downplay the importance of human rights, and that legislation should focus on user needs rather than speculative futuristic scenarios. They also noted that robots lacked the autonomy to take part in society on their own. Progress in AI increased interest in the topic. Proponents of AI welfare and rights often argue that AI sentience, if it emerges, would be particularly easy to deny. They warn that this may be a moral blind spot analogous to slavery or factory farming, which could lead to large-scale suffering if sentient AI is created and carelessly exploited.
Generative artificial intelligence (GenAI) is a subfield of artificial intelligence (AI) that uses generative models to generate text, images, videos, audio, computer code or other forms of digital data. These models learn the underlying patterns and structures of their training data, and use them to generate new data in response to input, which often takes the form of natural language prompts. The prevalence of generative AI tools has increased significantly since the AI boom of the early 2020s. This boom was made possible by improvements in deep neural networks, particularly large language models (LLMs), which are based on the transformer architecture. Generative AI applications include chatbots such as ChatGPT, Claude, Microsoft Copilot, DeepSeek, Doubao, Google Gemini, Grok, Kimi and Qwen; text-to-image models such as DALL-E, Firefly, Stable Diffusion, and Midjourney; and text-to-video models such as Veo, LTX and Sora. Companies in a variety of sectors have used or proposed the use of generative AI, including those in software development, healthcare, finance, entertainment, sales and marketing, screenwriting, and product design. Generative AI has been used for cybercrime, and to deceive and manipulate people through fake news and deepfakes. Generative AI models have been trained on copyrighted works without the rightholders' permission. Many generative AI systems are reliant on large-scale data centers, whose environmental impacts include electronic waste, consumption of fresh water for cooling, and high energy consumption that is estimated to be growing steadily.
The submucosa consists of a layer of dense irregular connective tissue with large blood vessels, lymphatics, and nerves branching into the mucosa and muscular layer. It contains the submucosal plexus, an enteric nervous plexus, situated on the inner surface of the muscularis externa.
== Pharmacokinetics == The pharmacokinetics of synephrine were studied by Hengstmann and Aulepp, who reported a peak plasma concentration at 1–2 hours, with an elimination half-life (T1/2) of ~ 2 hours.
Sources: en.wikipedia.org
Legal status varies by country, but cardarine is not approved as a medicine in major jurisdictions. It is often sold as a research chemical, a category that may not be lawful for human use. Buyers should check local laws and product labels carefully.
Anti-doping laboratories use LC-MS/MS to detect GW501516 and its metabolites, usually in urine. The method can identify the parent compound at low concentrations. Detection windows vary with dose and individual factors.
No, cardarine has no approved medical uses in major jurisdictions. Early research explored metabolic conditions, but those programs were discontinued. It is not a registered treatment for any disease.
Anti-doping and clinical laboratories commonly use liquid chromatography-tandem mass spectrometry. The method can identify GW501516 and its metabolites in urine or blood. Detection depends on sample timing and the amount present.